<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>hello vue</title>
<style type="text/css">

</style>
</head>
<body>





<div id="app">

  <input type="text" v-model='first' >+
  <input type="text" v-model='last'  >=
  <input type="text" v-model='full'>
{{fullname}}
  
</div>









<br>
<script src="vue.js"></script>
<script src="vue-router.js"></script>
<script type="text/javascript">

var  vm= new Vue({
  el: '#app',

  data: {
    first:'',
    last:'',
    full:'',
     
  },

  methods:{
    
  },

  computed:{//计算属性
    'fullname':function(){
      console.log("123")
      return this.full = this.first+this.last
    }
  }



})





</script>

  
</body>
</html>